Carton joint assembly and method of producing same



Nov. 1, 1955 CARLSON 2,722,366

CARTON JOINT ASSEMBLY AND METHOD OF PRODUCING SAME 2 Sheets-Sheet 1 Filed June 19, 1952 IN VEN TOR HEW/0E E (/76; 50/V Nov. 1, 1955 A. E. CARLSON 2,722,

CARTON JOINT ASSEMBLY AND METHOD OF PRODUCING SAME 2 Sheets-Sheet 2 Filed June 19, 1952 IN V EN TOR. FEfl/UE 5. 64 6A SO/V M a United States Patent Ofifice 2,722,366 Patented Nov. 1, 1955 CARTON JOINT ASSEMBLY AND METHOD OF PRODUCING SAME Arthur E. Carlson, Troy, Ohio Application June 19, 1952, Serial No. 294,335

9 Claims. (Cl. 229-49) This invention relates to a joint assembly and the method of producing the same and more particularly to a joint of a carton made from cardboard or corrugated board, although not necessarily so limited, in that the joined parts may be made of any suitable material.

This application is a continuation-in-part of my copending application Serial No. 109,482, filed August 10, 1949, for Reenforced Paper Articles, now Patent No. 2,610,936, patented September 16, 1952. In this patent the manufacture of a stay tape has been described to include paper stock of substantial width having reinforcing elements extending thereacross. After the reinforcing elements have been applied to the paper stock, this stock is cut into strips of appropriate width for corner stay tape.

Cartons utilizing stay tape for securing the manufacturers joints together are generally provided with a stay tape including a layer of paper adhesively secured to the adjacent portions of the material from which the carton is made. The stay tape may be reinforced or laminated and if so, a layer of paper constitutes one of the lamina, which layer of paper is provided with a gummed surface or receives adhesive for securing the stay tape to the adjacent portions of the carton. It can readily be seen that if this layer of paper splits, the reinforcing material is then of no avail, in that the reinforcing material is split away from the portion of the paper that remains adhesively secured to the carton. When this takes place, a very thin web of paper is the only bond between adjacent portions of the carton and therefore readily fails. Splitting of the web of paper adhered to the carton in both cloth filled duplex stay tapes and in reinforced paper laminated stay tapes is well known in the industry and much effort has been given to the solution of this problem.

In the patent to Angier 1,195,430, he suggests threads secured in an adhesive layer on one face of a sheet of paper. He follows this with the explanation that When the threads are introduced between the paper layers, however, they are protected against displacement by the layers and permit smooth and uninterrupted surfaces to be had on opposite sides of the tape. This statement negatives any thought on behalf of Angier of applying the reinforcing elements directly to the sides of the carton.

An object of this invention is to provide a joint assembly that includes stay tape provided with reinforcing elements adhesively secured directly to the adjacent portions of the carton, the reinforcing elements being first secured to a web of paper; but this web of paper is located on the outside of the reinforcing elements when the stay tape is used, therefore there is no paper web separating the reinforcing elements from the carton, which web could split and remove the reinforcing elements as frequently happens in currently used stay tapes. In the event of paper splitting in the product of this invention, the reinforcing elements, plus whatever thickness of paper remains after splitting, are available to hold the carton joint together. These reinforcing elements may be of any suitable material, such as twisted or untwisted rayon filaments or other synthetic organic or inorganic, substantially continuous length filaments, or they may consist of fine strands of yarn, bands of material including strips of paper cut parallel to the direction of maximum tensile strength, strips of plastic or strips or strands of metal.

Other objects and advantages reside in the construction of parts, the combination thereof and the mode of operation, as will become more apparent from the following description.

In the drawings:

Figure 1 is a perspective view of a carton having a joint held together by reinforced stay tape.

Figure 2. is a fragmentary, cross sectional view, taken substantially on the line 2-2 of Figure 1.

Figure 3 is a fragmentary, enlarged view of a portion of a joint, disclosing part of the paper split away.

Figure 4 is a fragmentary, perspective view of one type of stay tape.

Figure 5 is another perspective view of a stay tape, wherein the reinforcing elements have been de-bossed.

Figure 6 discloses another type of stay tape wherein the reinforcing elements consist of at least two types of material.

Figure 7 is another perspective view of a reinforced stay tape utilizing two types of material.

Figure 8 discloses another type of reinforcing material and illustrates the steps of producing same.

Figure 9 is a fragmentary view of another type of stay tape having substantially continuous length filaments extending transversely across the stay tape, the filaments cooperating to cover substantially all of one side of the backing sheet.

Figure 10 is another type of stay tape that is elastic, so as to be adapted to absorb shock.

Figure 11 is a cross sectional view of a joint utilizing the elastic tape disclosed in Figure 10.

The reinforced stay tape joint assembly for a carton, or for any other purpose, consists of a sheet of material, such as paper, having adhesively secured to one side thereof a plurality of reinforcing elements transversely disposed, the reinforcing elements and any portion of the sheet of material that may exist between the reinforcing elements being adhesively secured to the sides of a carton blank, which sides cooperate to form a joint, so that the reinforcing elements are applied directly against the sides of the carton, the sheet of material overlying the reinforcing elements and the sides of the carton. These reinforcing elements may be any suitable material, either twisted or untwisted filaments, or they may consist of strips of material having the desired characteristics. These transversely placed strips of material forming the reinforcing elements may consist of paper, fabric, plastic, metal, or any other suitable material, as will appear more fully from the description that follows. The reinforcing elements need not all be made from the same type of material. Some may consist of yarn interposed between strips of material. Others may consist of strips of paperand ribbons consisting of filaments twisted or untwisted.

Referring to the drawings, the reference characters 20 and 22 indicate the sides of a carton 24, the sides being joined along the corner 26. The sides are secured together by a stay tape 30, consisting of a plurality of reinforcing elements 32 and a strip of longitudinally extending sheet material such as paper 34. The reinforcing elements 32 are adhesively secured to the sheet of paper 34 and the reinforcing elements are adhesively secured to the sides 20 and 22 of the carton. The portions of the paper 34- located between the reinforcing elements 32 are also adhesively secured to the walls of the carton. These reinforcing elements 32 may be made from various types of materials, either organic or inorganic, either homogeneous or composite. These reinforcing elements 32 may be positioned on one side of the paper, as shown in Figure 4, or they may be de-bossed, as shown in Figure 5.

These reinforcing elements may consist of any suitable reinforcing material. For example, each of these reinforcing elements may consist essentially of a multiplicity of fine substantially continuous and substantially untwisted filaments arranged in close side by side relation in a plurality of levels or layers to form a thin band equal in thickness to the combined thickness of a plurality of said filaments. Adhesive material, substantially saturating the reinforcing elements or bands, is used to secure said bands to the web surface and to secure the levels of filaments in compact and substantially flat form. Additional adhesive material overlies the bands or elements and the areas on the web surface between the bands for bonding the web and the bands directly to the edge portions of an adjacent blank. Each band is substantially greater in average width than the maximum thickness thereof to provide a correspondingly exposed wide area for intimate adhesive contact between the bands and the edge portions of the blank, so as to retain the bands in reinforced connecting relation between the edges of the blank in the event of splitting of the web from the blank.

For purposes of this invention, the reinforcing elements may be de-bossed to provide a flush surface or they may substantially cover the paper, thus providing a flush surface, or, if applied to the paper in spaced relation, the reinforcing elements may be of very low caliper, so as to present a substantially flush surface, or a filler material may be used between the spaced reinforcing elements to provide a substantially fiat surface so as to obtain a satisfactory adhesive bond of the reinforced side of the tape to the carton side. When the reinforcing elements are de-bossed, the surface in contact with the carton is flush, as clearly shown in Figure 5. The reinforcing elements may be arranged in spaced relation, as shown in Figures 4 and 5, or they may be arranged side by side, as shown in Figures 6, 7 and ll. In Figures 6 and 7 two types of reinforcing material have been used.

As may best be seen by referring to Figure 6, reinforcing strips or ribbons 40 and 4-2 are adhesively secured to a sheet of paper, or other suitable material 44. The strips 40 may consist of strips of paper or they may consist of a plurality of continuous length filaments, either organic or inorganic filaments. The reinforcing elements 42 may consist of low twist yarn or highly twisted material.

In Figure 7 a short piece of stay tape has been shown, wherein strips of solid material 50 are interposed between reinforcing elements 52 of continuous length twisted or untwisted filaments, such as rayon, nylon or glass fibers. The strips 50 and the reinforcing elements 52 are secured to one side of a backing sheet of material 54, such as paper. Although in Figure 7 it appears as though small channels are located between the ribbons 50 and the reinforcing elements 52, in actual practice these channels may be irregular in width and in places non-existent where the two types are in contact. The ribbons 50 may be made from strips of paper cut in the machine direction of the paper and applied transversely to the machine direction of the backing sheet 54. This is done to obtain the tensile strength of the strips 50 to reinforce the sheet 54, which is Weakest or has the least tensile strength in the crosswise direction.

In Figure 8 a plurality of twisted reinforcing elements 60 have been applied to one side of a sheet of material 62, which, again, may be paper or any other suitable material. These groups of yarns 60 may be passed through adhesive material between their source of supply and the work station where the groups are applied to the sheet 62. When applied, the yarns of a group are in a compact bundle a. After the groups have been applied to the sheet 62, but before the adhesive has fully set, pressure is exerted upon the groups to spread them out, so as to cause the tiny yarns to lie substantially side by side, as shown at 64. For the purpose of illustration, only three tiny twisted yarns have been shown. The number of yarns is not limited to three, in that each group may consist of a considerable number of tiny twisted yarns. For example, if tiny twisted nylon yarns of about 40 denier each were used, the number of yarns in each group would number in the neighborhood of 10 to 20. If smaller twisted yarns were used, there would be more of them in each group, and vice versa. By using tiny twisted yarns of such fine caliper, it is possible to allow some yarns to overlie others without the average caliper of the group being excessive.

Again, these twisted reinforcing elements are applied directly to the sides of the carton. In the event the paper splits, as shown at in Figure 3, the reinforcing elements retain the joint in connection. Furthermore, by this arrangement, the paper of the tape may become Wet with moisture, so as to become pulpy and have little or no strength, and the reinforcing elements will still be available to retain the sides of the carton, especially when a water resisting adhesive has been used to bond the stay tape to the carton.

In Figure 9 the reinforcing elements have been applied in spaced relationship to the sheet material, such as paper 82, in groups. After they have been applied to the sheet of material, but before the adhesive material has set, a pressure instrument may be applied, so as to spread the reinforcing members forming the groups into a substantially continuous layer, as shown at 86, thus destroying the spaced relationship of the groups when first applied. The reinforcing elements may be adhered by a suitable adhesive, such as a water impervious adhesive, as for example, a latex base adhesive, which has the proper viscosity for saturating the filaments forming each reinforcing element.

In the modification disclosed in Figures 10 and 11, a reinforced tape assembly has been shown that is elastic. This assembly may include a strip of stretchable backing sheet 100, such as crepe paper, that has been creped in two directions diagonally to the longitudinal direction of the paper, as indicated by the diagonal lines in Figure 10. This stretchable backing sheet may also consist of other types of stretchable sheet material, such as is made by adding latex in the manufacture of stretchable paper. A plurality of stretchable reinforcing elements 102 are applied to one surface of the crepe paper and extend transversely across the strip of crepe paper. The reinforcing elements 102 may consist of nylon filaments or any other suitable stretchable material and are secured to one side of the crepe paper by a sufficiently elastic adhesive material, such that when the tape is subjected to transverse tensile forces, that is, subjected to tensile forces in the direction of the reinforcing elements 102, the crepe paper, together with the reinforcing elements, will stretch in unison. The portion 112a of Figure 11 shows that the stay tape is not entirely in contact with the carton sides and this area is thus free to stretch.

To improve upon that construction, adhesive material may be applied in strips along the margins 104 and 106, leaving a zone 112 between the margins 104 and 106 that has no adhesive material applied thereto. Then, by applying the stay tape to the sides of the carton, as shown in Figure 11, the margins 104 and 106 will be adhesively attached to the sides 108 and 110 respectively. The portion 112 that has no adhesive material applied thereto extends over the corner or joint between the sides 108 and 110. This permits a broader stretching area of the stay tape in that unadhered portion extending across the corner or joint and in the unadhered area to each side of a joint where no adhesive bond between the carton sides and the stay tape exists. By this arrangement the stay tape may yield in response to a shock or an impact without failure of the joint. Furthermore, in the event the stresses applied to the sides of the carton are sufiicient to cause the sides to bulge slightly, the stay tape can stretch without failure of the stay tape overlying the joint. The adhesive used to cover the margins 104 and 106 is selected from an adhesive material having sufficient tenacity to hold the reinforcing elements in contact with the sides of the carton without failure, even though the stresses may be sufficient to stretch the reinforcing elements and the paper in the immediate vicinity of the joint where no adhesive bond exists between carton and stay tape.

Although the preferred embodiment of the device has been described, it will be understood that within the purview of this invention various changes may be made in the form, details, proportion and arrangement of parts, the combination thereof and mode of operation, which generally stated consist in a device capable of carrying out the objects set forth, as disclosed and defined in the appended claims.

Having thus described my invention, I claim:

1. In a carton of the character described including a blank having a pair of adjacent edges adapted to be connected to form a joint, means forming a reinforced connection between said edges comprising a paper Web overlying said joint and extending longitudinally therealong, a plurality of elongate reinforcing elements positioned between said web and said blank and extending transversely of said web and said joint in spaced relation, each of said reinforcing elements consisting essentially of a multiplicity of substantially continuous and substantially untwisted filaments arranged inclose side by side and overlying relation to form a thin band, adhesive material substantially saturating each said band and securing said filaments therein to each other and to the adjacent surface of said web in compact form minimizing the projection of each said band out of the plane of said web surface, additional adhesive material overlying said bands and the areas of said web surface therebetween and bonding said web and said bands directly to the portions of said blank adjacent said edges, and each said band being of substantially greater average width than the maximum thickness thereof to provide a correspondingly exposed wide area for intimate adhesive contact between said band and said portions of said blank to retain said bands in reinforced connecting relation between said blank edges in the event of splitting said web from said blank.

2. In a carton of the character described including a blank having a pair of adjacent edges adapted to be connected to form a joint, means forming a reinforced connection between said edges comprising a paper web overlying said joint and extending longitudinally th'erealong, a plurality of elongate reinforcing elements positioned between said web and said blank and extending transversely of said web and said joint in spaced relation, each of said reinforcing elements consisting essentially of a multiplicity of fine substantially continuous and substantially untwisted filaments arranged in close side by side relation in a plurality of levels to form a thin band equal in thickness to the combined thickness of a plurality of said filaments, adhesive material substantially saturating each said band to secure said band to said web surface and to secure said levels of filaments together in compact and substantially flat form, additional adhesive material overlying said bands and the areas of said web surface therebetween and bonding said web and said bands directly to the portions of said blank adjacent said edges, and each said band being of substantially greater average width than the maximum thickness thereof to provide a correspondingly exposed wide area for intimate adhesive contact between said band and said portions of said blank to retain said bands in reinforced connecting relation between said blank edges in the event of splitting of said web from said blank.

3. The method of producing a carton of the character described having a pair of adjacent edges adapted to be connected to form a joint, comprising applying to one surface of a paper web a plurality of reinforcing elements extending transversely of said web in spaced relation, each of said reinforcing elements consisting essentially of a multiplicity of fine substantially continuous and substantially untwisted filaments arranged in close side by side and overlying relation to form a thin band, causing said adhesive to set in bonding relation with said filaments and said web surface while maintaining the width of each said band substantially greater than the maximum thickness thereof to provide a correspondingly wide area for intimate adhesive contact between said adhesive-saturated band and said web surface and a similarly wide exposed area on the outer surface of each said band, applying a layer of adhesive material to said exposed surfaces of said bands and to the portions of said web surface intermediate said bands, and bonding said reinforced web to said edges of said blank by means of said adhesive layer with said reinforcing elements extending transversely of said blank edges between said web and said blank in directly bonded relation with said blank to cause said bands to be retained in reinforcing connecting relation between said blank edges in the event of subsequent splitting'of said web from said blank.

4. The method of producing a carton of the character described having a pair of adjacent edges adapted to be connected to form a joint, comprising applying a layer of adhesive material to the reinforced surface of a paper web having a plurality of reinforcing elements bonded thereto and extending transversely thereof in spaced relation, each of said reinforcing elements consisting essentially of a multiplicity of fine substantially continuous filaments arranged in substantially untwisted side by side and overlying relation to form a thin band and an adhesive material substantially saturating said band and securing said filaments therein to each other and to said web surface in compact form maintaining the width of each said band substantially greater than the maximum thickness thereof to provide a correspondingly wide exposed area on the outer surface of said band, said layer of adhesive material being applied to said exposed surfaces of said bands as well as to the portions of said web surface intermediate said bands and bonding said reinforced web to said edges of said blank by means of said adhesive layer with said reinforcing elements between said web and blank and extending transversely of said blank edges in directly bonded relation with said blank to cause said bands to be retained in reinforcing connecting relation between said blank edges in the event of subsequent splitting of said web from said blank.

5. A reinforced stay tape carton joint assembly, including a carton having a pair of adjacent edges adapted to be connected to form a joint, a single strip of kraft paper, a plurality of reinforcing elements each consisting of a multiplicity of fine substantially continuous and substantially untwisted organic synthetic filaments forming a compact thin ribbon of substantially greater width than thickness, the thickness of each said ribbon being less than the thickness of the paper, the reinforcing elements being arranged at spaced intervals upon the paper, adhesive material originally drawn into the ribbon by capillary attraction in sufiiicent quantity to saturate the ribbon and bonding all the filaments to one another and to the paper, the adhesive material on the paper being confined to the areas covered by the ribbon, and adhesive material applied to the exposed surfaces of the ribbons and the exposed areas of the paper between the ribbons securing the stay tape to the carton edges so that in the event the paper is split and thereby substantially removed from the carton the reinforcing elements will remain adhered to the carton, said ribbons being so thin that only an economical amount of adhesive need be used to bond the paper and the ribbons intimately and directly to the carton.

6. A stay tape carton joint assembly including a carton having a pair of edges adapted to be connected to form a joint, a single strip of paper having paper fibers that are adhesively bonded, a plurality of reinforcing elements at spaced intervals along one face of the paper strip which extend substantially transversely on the paper strip; each said element consisting of a multiplicity of fine, continuous, contacting substantially parallel originally loose filaments, the filaments being grouped in a substantially untwisted thin compact ribbon having a thickness equal to that of several filaments and having a width many times greater than its thickness, means adhesively bonding the filaments of each said element together and to said face of said paper strip, and adhesive material overlying said face and said reinforcing elements bonding said paper strip and said reinforcing elements directly to the surface of the carton edges with said elements adhesively secured to the carton edges forming the joint to retain said reinforcing elements adhered to said carton edges event though the major portion or substantially all of the paper of the strip is split and removed from the carton leaving substantially only the reinforcing elements to hold the carton joint from opening.

7. A stay tape carton joint assembly including a carton having a pair of adjacent margins of the sides of the carton, a single strip of paper having paper fibers that are adhesively bonded, a plurality of reinforcing elements at spaced intervals along one face of the paper strip which extend substantially transversely on the paper strip, each said reinforcing element consisting of a multiplicity of fine, substantially continuous and susbtantially untwisted organic synthetic filaments, each said reinforcing element being substantially saturated with an adhesive material bonding said filaments therein together and to said face of said paper strip and maintaining said reinforcing elements in compact thin shape with a corresponding wide exposed area, and additional adhesive bonding said face of said strip and said reinforcing elements directly to the surface of the carton with said reinforcing elements cooperating with said paper strip to hold the sides of the carton and with said reinforcing elements adhesively secured to the carton sides forming the joint to retain said reinforcing elements adhered to the carton sides forming the joint even though the major portion or substantially all of the paper of the strip is split and removed from the carton leaving substantially only the reinforcing elements to hold the carton joint from opening.

8. In a carton of the character described including a blank having a pair of adjacent edges adapted to be connected to form a joint, means forming a reinforced paper stay tape connection between said edges comprising a paper web overlying said joint and extending longitudinally therealong, a plurality of elongate ribbon-like reinforcing elements positioned between said web and said blank and extending transversely to the surface of said web in spaced parallel relation running from edge to edge of said web and spanning said joint, each of said reinforcing elements consisting essentially of a plurality of filament members arranged in close side by side relation to form a thin band, adhesive material substantially saturating each said band and securing said members therein to each other and on the adjacent surface of said web in compact form minimizing the projection of each said band above the plane of said Web surface, additional adhesive material overlying said bands and the areas of said web surface therebetween and bonding said web and said bands directly to the portions of said blank adjacent said edges, and each said band being of substantially greater average width than thickness to provide a wide area for adhesive contact between said bands and said portions of said blank.

9. A reinforcing tape carton joint assembly including a carton having a pair of adjacent edges adapted to be connected to form a joint, a strip of kraft paper, a plurality of elongated rectilinear ribbon-shaped reinforcing elements each comprising a flattened bundle of filaments consisting of tiny twisted yarns and arranged in close side-by-side relation forming a compact thin ribbon of substantially greater width than thickness the reinforcing elements being positioned transversely of the strip and arranged at spaced intervals upon the paper, adhesive material orginally drawn into the ribbon by capillary attraction in sufficient quantity to saturate the ribbon and bonding all the filaments to one another and to the paper, the adhesive material on the paper being confined to the areas covered by the ribbon, and adhesive material applied to the exposed surfaces of the ribbons and the exposed areas of the paper between the ribbons securing the stay tape to the carton edges so that in the event the paper is split and thereby substantially removed from the carton the reinforcing elements will remain adhered to the carton, said ribbons being so thin that only an economical amount of adhesive need be used to bond the paper and the ribbons intimately and directly to the carton.

References Cited in the file of this patent UNITED STATES PATENTS 855,322 MacCallum May 28, 1907 867,041 Hoffmann Sept. 24, 1907 1,039,363 Chapin Sept. 24, 1912 1,195,430 Angier Aug. 22, 1916 1,351,374 Crowell Aug. 31, 1920 1,866,513 Ballard July 5, 1932 1,901,094 Gabosch Mar. 14, 1933 2,026,194 Smith Dec. 31, 1935 2,283,349 Angier May 19, 1942 2,295,439 Voigtman Sept. 8, 1942 2,604,424 Mathes July 22, 1952 2,610,936 Carlson Sept. 16, 1952 2,636,835 Boulware Apr. 28, 1953 

